Matrix film for the production of colored copies



Patented July 18,

MATRIX FILM FOR THE PRODUCTION OF COLORED COPIES Gard Heymer, Wolfen,Krels Bitterield, Germany,

assignor to General Aniline & Film Corporation, New York. N. Y.. acorporation of Delaware 1% Drawing. Application September 14,1940, Se-'rlal No. 356,835. In Germany May 5, 1939 6 Claims.

This invention relates to matrix film for the production of coloredcopies.

The matrix films which are destined for the I production of printingreliefs are generally .exposed through the emulsion carrier, developedwith a hardening developer and washed out in warm water, so that afterthe washing process a relief'remains on those places only, where silverwas present. The relief may be also obtained by developing with anordinary developer and after treating with bichromate. However, withoutspecial precautions the relief becomes too high and the gradationconsequently too steep. In order to prevent this, there is ordinarilyadded to the emulsion layer a yellow or red dyestufi' ..vide a methodfor the preparation of colored reproductions with the aid of matrixfilms.

1 color tinge which absorbsblue.

Other and more specific objects will appear from the followingdisclosure.

The matrix films hitherto known were destined to be exposed under blackand white originals and consequently they were not specially sensitized.The new material on the other hand is designed for obtaining the three.separation pictures from the colored originals directly on the matrixfilm.

The following two ways are possible:

(1) One sort of film is used for all three separation pictures. Theemulsion is dyed with a black dyestuff in a suitable density. Theemulsion carrier also is tinged with a neutral gray dyestufi in such amanner, that it possesses a transparency of about 70%. In this way oneavoids the halation by reflection which always happens, when a film isexposed through the emulsion carrier. Besides being sensitized for bluelight the film is sensitized for green and red light, while insuringthat the sensitizing maxima in the green and in the red correspond asmuch as possible to the absorption maxima of the purremoved either bythe treating baths or by a special bath. If for the development of thematrix films there is used a developer which hardens the gelatin at theplace of the photographic image, also colloidal silver may be added tothe emulsion in place of the black dyestufi. This, however, is notpossible, when films are afterwards hardened with the aid of bichromate,sinceunder these circumstances the silver added to the emulsion wouldharden the entire emulsion layer.

(2) Three different types of films are used for the separation pictures.

(a) Blue separation picture.-Matrix films similar to the materialhitherto used possessing a Emulsion not sensitized. Dyeing of theemulsion carrier'with grey or blue absorbing dyestuif.

(b) Green separation picture.Dyeing of the green sensitized emulsionwith a green absorbing dyestuilf, for instance purple, the maximum ofwhich corresponds to the sensitizing, maximum. Dyeing of the emulsioncarrier with a neutral gray or green absorbing, for instance purpledyestufi. Y

(0) Red separation picture.--Emulsion red sensitized and'dyed with a redabsorbing dyestuil, for instance blue-green. Antihalation layer whichmust be located between the emulsion layer and the original, forinstance, between the carrier and the emulsion or nn'the non-emulsifiedside of the film. The copying must be done with a point-light source, inorder to insure sharpness in spite of the distance between original andcopying material. Another possibility is to copy (enlarge) optically.For the dyeing of the emulsionpreferablysuch dyestuffs are to be usedwhich are easily dissolved or destroyed in the treating baths. Naturallyalso such dyestuffs can be. employed which have tobe destroyed by aspecial bath.

The matrix films thus obtained from them!- ored originals are dyed in aknown manner and are transferred in an accurately registered form" onblanks according to the known imbibition process. v Y

It is also possible to remove the colored reliefs from their carrier andto arrange them firmly and in accurate registration one on top of theother; on another final transparent or reflecting carrier. In this casethere may be used for the dyeing of the emulsion besides theaforementioned dyestufls also'such substances which are not destroyed,but remain in the relief andserv for the building up of the color image.a

What I claim is: 1. A process of producing colored copies on matrix filmwhich comprises exposing three ma,-

trix films each comprising an emulsion carrier I and a singlephotographic emulsion layer thereon which is panchromatically sensitizedand contains a readily removable from gray to black fllter dyestufl tothe different primary color lights 1 proceeding directly fromthree-color separation originals and processing the-exposed films in themanner usual with matrix film.

2. The process as defined in claim 1 wherein the emulsion carrier 01'each matrix film contains as an antihalation agent a neutral gray dyestun.

3. The process as defined in claim 1 w the emulsion carrier of eachmatrix 'nlm cone tains as an antihalation agent a neutral gm dyestufl ata transparency of from 0.5 to ;0.9. s

4..The process as defined in claim lvwherein' the exposureoi each matrixfllm 'to the origlnal three-color separations is effected by means orseparation filters transmitting-narrow spectral regions.

5. The process as defined in claim 1 wherein the maxima of the green andred-sensitivities of each emulsion correspond to-the absorption maxlmaoi the purple and blue-"green dyestuils oi

